Answer:
12 cm x 15 cm
Step-by-step explanation:
if the picture frame thickness is x,
then the frame dimension would be (8+2x) cm by (11+2x) cm
area is (8+2x)(11+2x)=180
solve for x, x= 2, -23/2
x is thickness, so should be >0, so x=2
frame dimension: 12 x 16